As costs of energy increase along with concerns about global warming due to consumption of fossil fuels to generate energy, there is an every increasing need for more efficient lighting technologies. These demands, coupled with rapid improvements in semiconductors and related manufacturing technologies, are driving a trend in the lighting industry toward the use of solid state light sources, such as light emitting diodes (LEDs) or the like, to produce light for general lighting applications, as replacements for incandescent lighting and eventually as replacements for other older less efficient light sources.
However, in this age of ever increasing concern over energy consumption, there is always a need for techniques to still further improve efficiency of solid state lighting fixtures or systems. Manufacturers of the LEDs continue to try to improve performance efficiency of the LEDs, and lighting fixture manufacturers continue to improve the optical design of the lighting fixtures to provide desirable light output characteristics (e.g. high quality white light) with minimal loss of light power in the optic(s) of the fixtures.
Another area of concern regarding efficiency relates to the electrical circuitry that drives the LEDs. Although modern driver and power supply circuits are fairly efficient, some power is consumed within the power supply before transfer as drive current to the LEDs.
The above developments not withstanding, there is still room for improved efficiency in LED lighting. For example, some power is still wasted in the LED power supply. Even a small reduction in such power loss (increase in efficiency) can provide a significant overall improvement in the performance of the LED lighting system. Hence, a need exists for still further improvement in the power supply circuitry of a LED lighting system.